Thanks Scott.
Mixed up heads. Who knew?  lol

I asked mostly on behalf of the OP though my 2.1 I recently went
through a similar issue.
Turned out the blue cap on expansion tank had a failed valve; I could
blow-suck air through
it. New cap seems to have solved the issue.
My original concern was that compression or exhaust stroke was pumping
air into the cooling system.

But your point on engine history is really important. I'd assumed the
engine on my bus was
original. It could be anything but that. These rigs are so old now
some having at least a
few former owners. And you never know what work was done or how well
it was done.
A friend of mine had her 1.9 WBX repaired by a mechanic who'd never
laid hands on a WBX.
From what I can see, he took his time and likely used the "Right
Stuff" or similar at coolant
jacket seal at each head. But he has yet to provide even a work order
for what was done.
I'm pushing her to get that information.
And this was from a professional shop.
It might be fine but who knows.

Never "assume" ?

Neil.

On 6/18/16, Scott - IMAP <scottdaniel@turbovans.com> wrote:

> Supposedly the AMC heads are a much better casting not prone to cracks (
> tho they come with cheaper valves and retainers I gather ) .
>
> I haven't seen any VW heads crack ....
> I'd probably focus on that one if any problems tho.
> Make sure your VW head, and both heads are  for a 2.1.
>
> One 'rebuilt'  1.9 engine I ended up with had a 1.9 head on one side and
> a 2.1 one on the other , until I got that straightened out.
>
> If you personally don't know the exact history of what you have ..
> you never know what you're going to find.   Could be anything.
>
> Scott

--
Neil n

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